1. Field of the Invention
This invention relates to computer networks, and more particularly to a distributed trust mechanism for peer-to-peer networking environments.
2. Description of the Related Art
Trust is at the core of most relationships between human beings. The parameters of trust are often personal, and thus, decentralization is the nature of trust, because each individual has his/her own opinions. On a decentralized network, such as a Peer-to-Peer (P2P) network, users may see from where information arrives, as well as communicate their opinions on both the information they have acquired and the peers who are its source. These personal opinions may be collected, exchanged, and evaluated. Furthermore, these opinions, when evaluated, may be used as guidelines for searching for information, and recommending information sources, thus, creating decentralized, personalized “Webs of Trust.”
When such a decentralized trust model is implemented on a P2P topology, trust between peers may begin to mirror those real-world relationships with which users are familiar, and may permit software engineers to craft interfaces to the underlying trust model that are both understandable and usable. Trust becomes a social contract with social implications for the participants. Each such peer may develop a reputation among his peers, which may be the basis for P2P trust relationships.
In current trust or reputation models, the degree of trust is calculated with parameters such as performance, honesty, reliability, etc., of a given peer. If a peer cheats at playing cards, for example, the peer might be deprived of his ability to authenticate and join another card game.
However, for a group of people interested in cooking, the above measurement may be too biased towards personal risk and not content, and may thus be of little use. Hence, for a group such as a cooking group, it may desirable that trust be biased towards data relevance, or the quality of recipes. Trust may have multiple components or factors, and a factor of trust which is based on the group's interests and/or group content relevance, may be important.
Prior art implementations for certificate distribution, such as SSL and TLS, typically require certificates to be signed by recognized, trusted certificate authorities to both establish identity, and exchange public keys for public-key algorithms such as RSA and Diffy-Hellman. In a peer-to-peer network, it may be undesirable to require every participating peer to acquire, i.e., pay for, a Certificate Authority signed certificate in order to implement, for example, peer-to-peer TLS. In some embodiments, peer-to-peer zero-dollar-cost certificates may be desirable.
The ability to move one's private security environment from device to device may be desirable. For example, having multiple identities may be confusing and may add unwanted complexity to a security model. Since a private security environment may include information such as a user's private key, trusted root certificates, and peer group credentials, it may be desirable for mobility to be under the constraints of strong security. If a private key is no longer private, one's security environment, and all of the associated relationships may need to be recreated from zero.
The IETF's (Internet Engineering Task Force) SACRED Working Group is working on the standardization of a set of protocols for securely transferring credentials among devices. A general framework is being developed that may provide an abstract definition of protocols which may meet the credential-transfer requirements. This framework may allow for the development of a set or sets of protocols, which may vary from one another in some respects. Specific protocols that conform to the framework may then be developed.
Peer-to-Peer Computing Environment
Peer-to-peer (P2P) computing, embodied by applications like Napster, Gnutella, and Freenet, has offered a compelling and intuitive way for Internet users to find and share resources directly with each other, often without requiring a central authority or server. The term peer-to-peer networking or computing (often referred to as P2P) may be applied to a wide range of technologies that greatly increase the utilization of information, bandwidth, and computing resources in the Internet. Frequently, these P2P technologies adopt a network-based computing style that neither excludes nor inherently depends on centralized control points. Apart from improving the performance of information discovery, content delivery, and information processing, such a style also can enhance the overall reliability and fault-tolerance of computing systems. FIG. 1A illustrates two peer devices 104A and 104B that are currently connected. Either of the two peer devices 104 may serve as a client of or a server to the other device. FIG. 1B illustrates several peer devices 104 connected over the network 106 in a peer group. In the peer group, any of the peer devices 104 may serve as a client of or a server to any of the other devices.